The present invention relates to determining differences between two or more models.
Comparisons between items such as files are conventional. Products have been provided that compare files such as word processing files and indicate differences between each of the files. Such comparisons may be made since the problem domain is known and the semantic content of the files is understood. The differences between the two files provided by such comparisons are acceptable.
A need exist, however, to compare and obtain the difference between items such as models where the problem domain is unknown and the semantic content of the models is not understood. Accordingly, a comparison can be made between models without having to know the specific format of the data, nor what the data represents. As a result, a generic comparison tool and method may be created.
An aspect of the present invention provides a method for comparing a first model and a second model. The method includes identifying metadata in the first and second model, and calculating a first set of signatures for objects of the metadata of the first model and a second set of signatures for objects of the metadata of the second model. The objects of the first model and the second model corresponding with each other have the same signatures. The method also includes determining which signatures of the first set of signatures match signatures of the second set of signatures. The method also includes determining for the matching signatures whether the objects associated with the signatures of the first set of signatures equal the objects associated with the signatures of the second set of signatures.
Another aspect of the present invention provides determining whether the objects associated with the signatures of the first set of signatures equal the objects associated with the signatures of the second set of signatures. The step of determining includes determining whether an owner of at least one object associated with the signatures of the first set of signatures matches an owner of at least one object associated with the signatures of the second set of signatures. The step of determining also includes determining whether at least one ownee of the at least one object associated with the signatures of the first set of signatures equal at least one ownee of the at least one object associated with the signatures of the second set of signatures. The step of determining also includes determining whether at least one non-reference property of the at least one object associated with the signatures of the first set of signatures equals at least one non-reference property of the at least one object associated with the signatures of the second set of signatures. The step of determining also includes determining whether at least one reference property of the at least one object associated with the signatures of the first set of signatures match at least one non-reference property of the at least one object associated with the signatures of the second set of signatures.